(1)Field of the Invention
The present invention relates to a lock-up clutch used in a torque converter for automobiles, and particularly, to a structure for connecting an output part of a clutch disk to a turbine of the torque converter.
(2) Description of the Prior Art
Lock-up clutches of a type concerning with the present invention are disclosed in U.S. Pat. No. 4,240,532, accepted Japanese Utility Model publication No. 61-28126, and Japanese Utility Model application No. 61-170593. In the lock-up clutches disclosed there, an input part of a clutch disk is connected to an output part through damper springs. The output part basically includes an annular body extending in a circumferential direction of the torque converter, and a plurality of claws projected from said annular body and engaging with the said springs. The annular body is welded to a rear or outer surface of a radially outer portion of a turbine shell.
In the above structures, since the output part of the clutch disk is an annularly continuous member having a large outer diameter, and further having a narrow radial width, i.e., a large inner diameter, the yield rate is low in the manufacturing process in which the annular member is blanked from a flat metal sheet.
Accordingly, it is an object of the invention to provided a structure, overcoming the above-noted problem.